1 US Gallon = 231 Cubic Inches So if you find out the cubic inches you can convert it to gallons. Example: If your tank is 3 ft wide by 2 ft deep and 2 ft high.
36 inches x 24 inches x 24 inches = 20736 cubic inches / 231 per gallon = 90 gallons
This size tank can hold up to 7,779.74 US gallons of water.
== 478.79 gallons, there are 7.481 gallons in a square foot. So that is 64 x 7.481== 478.79.==http://dictionary.reference.com/writing/styleguide/weights.html
Multiply the number of cubic feet in the tank by 7.5 to find gallons.
209.52 gallons. Lx Wx H /231 = GALLONS
A 20 Gallon tank can hold up to 20 gallons of water.
2000 gallons
About 157.1 gallons.
This tank will hold a maximum of 10,030 gallons of water.
886,174
10 ft X 10 ft square tank will hold 1000 cubic feet of water or 7480.51 gallons 10 ft round tank will hold 785 cubic feet of water or 5872.207 gallons
A 15 cubic foot tank will hold a maximum of about 112.2 gallons of water.
A 1,000 cubic foot tank holds up to 7,480 US gallons of water.